如何使用另一个较小数据帧的行索引显示或获取较大数据帧的行数据/值?

2024-03-29 12:59:30 发布

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我有一个熊猫数据帧(df2),它的列为Country/RegionDateNewConfirmed。我想使用列Country/Region下列出的国家,并在另一个行数更多的pandas数据框(df1)上查看它们的数据。我尝试了merge函数,但当我查看输出csv文件时,在前面的列名称Date_x和'Date_y'上添加了_x_y的各种新列

我只想得到新确诊病例的每个日期的国家列表和它们的不同值,以便以后绘制它们

我使用的数据是来自约翰·霍普金斯大学的新冠病毒-19数据集的净化/转换数据

这是我的df2(包含更多行)代码段:

<table> <tbody> <tr> <th> </th> <th> </th> <th>Country/Region</th> <th>Date</th> <th>NewConfirmed</th> <th>index_by_country</th> </tr> <tr> <td>1</td> <td>0</td> <td>Afghanistan</td> <td>2020-03-14</td> <td> </td> <td>1</td> </tr> <tr> <td>2</td> <td>1</td> <td>Afghanistan</td> <td>2020-03-15</td> <td>5.0</td> <td>2</td> </tr> <tr> <td>3</td> <td>2</td> <td>Afghanistan</td> <td>2020-03-16</td> <td>5.0</td> <td>3</td> </tr> <tr> <td>4</td> <td>3</td> <td>Afghanistan</td> <td>2020-03-17</td> <td>1.0</td> <td>4</td> </tr> <tr> <td>5</td> <td>4</td> <td>Afghanistan</td> <td>2020-03-18</td> <td>0.0</td> <td>5</td> </tr> <tr> <td>6</td> <td>5</td> <td>Afghanistan</td> <td>2020-03-19</td> <td>0.0</td> <td>6</td> </tr> <tr> <td>7</td> <td>6</td> <td>Albania</td> <td>2020-03-10</td> <td> </td> <td>1</td> </tr> <tr> <td>8</td> <td>7</td> <td>Albania</td> <td>2020-03-11</td> <td>2.0</td> <td>2</td> </tr> <tr> <td>9</td> <td>8</td> <td>Albania</td> <td>2020-03-12</td> <td>11.0</td> <td>3</td> </tr> <tr> <td>10</td> <td>9</td> <td>Albania</td> <td>2020-03-13</td> <td>10.0</td> <td>4</td> </tr> <tr> <td>11</td> <td>10</td> <td>Albania</td> <td>2020-03-14</td> <td>5.0</td> <td>5</td> </tr> <tr> <td>12</td> <td>11</td> <td>Albania</td> <td>2020-03-15</td> <td>4.0</td> <td>6</td> </tr> <tr> <td>13</td> <td>12</td> <td>Albania</td> <td>2020-03-16</td> <td>9.0</td> <td>7</td> </tr> <tr> <td>14</td> <td>13</td> <td>Albania</td> <td>2020-03-17</td> <td>4.0</td> <td>8</td> </tr> <tr> <td>15</td> <td>14</td> <td>Albania</td> <td>2020-03-18</td> <td>4.0</td> <td>9</td> </tr> <tr> <td>16</td> <td>15</td> <td>Albania</td> <td>2020-03-19</td> <td>5.0</td> <td>10</td> </tr> <tr> <td>17</td> <td>16</td> <td>Algeria</td> <td>2020-03-04</td> <td> </td> <td>1</td> </tr> <tr> <td>18</td> <td>17</td> <td>Algeria</td> <td>2020-03-05</td> <td>0.0</td> <td>2</td> </tr> <tr> <td>19</td> <td>18</td> <td>Algeria</td> <td>2020-03-06</td> <td>5.0</td> <td>3</td> </tr> <tr> <td>20</td> <td>19</td> <td>Algeria</td> <td>2020-03-07</td> <td>0.0</td> <td>4</td> </tr> <tr> <td>21</td> <td>20</td> <td>Algeria</td> <td>2020-03-08</td> <td>2.0</td> <td>5</td> </tr> <tr> <td>22</td> <td>21</td> <td>Algeria</td> <td>2020-03-09</td> <td>1.0</td> <td>6</td> </tr> <tr> <td>23</td> <td>22</td> <td>Algeria</td> <td>2020-03-10</td> <td>0.0</td> <td>7</td> </tr> <tr> <td>24</td> <td>23</td> <td>Algeria</td> <td>2020-03-11</td> <td>0.0</td> <td>8</td> </tr> <tr> <td>25</td> <td>24</td> <td>Algeria</td> <td>2020-03-12</td> <td>4.0</td> <td>9</td> </tr> <tr> <td>26</td> <td>25</td> <td>Algeria</td> <td>2020-03-13</td> <td>2.0</td> <td>10</td> </tr> <tr> <td>27</td> <td>26</td> <td>Algeria</td> <td>2020-03-14</td> <td>11.0</td> <td>11</td> </tr> <tr> <td>28</td> <td>27</td> <td>Algeria</td> <td>2020-03-15</td> <td>11.0</td> <td>12</td> </tr> <tr> <td>29</td> <td>28</td> <td>Algeria</td> <td>2020-03-16</td> <td>6.0</td> <td>13</td> </tr> <tr> <td>30</td> <td>29</td> <td>Algeria</td> <td>2020-03-17</td> <td>6.0</td> <td>14</td> </tr> <tr> <td>31</td> <td>30</td> <td>Algeria</td> <td>2020-03-18</td> <td>14.0</td> <td>15</td> </tr> <tr> <td>32</td> <td>31</td> <td>Algeria</td> <td>2020-03-19</td> <td>13.0</td> <td>16</td> </tr> <tr> <td>33</td> <td>32</td> <td>Andorra</td> <td>2020-03-17</td> <td> </td> <td>1</td> </tr> <tr> <td>34</td> <td>33</td> <td>Andorra</td> <td>2020-03-18</td> <td>0.0</td> <td>2</td> </tr> <tr> <td>35</td> <td>34</td> <td>Andorra</td> <td>2020-03-19</td> <td>14.0</td> <td>3</td> </tr> <tr> <td>36</td> <td>35</td> <td>Argentina</td> <td>2020-03-08</td> <td> </td> <td>1</td> </tr> <tr> <td>37</td> <td>36</td> <td>Argentina</td> <td>2020-03-09</td> <td>0.0</td> <td>2</td> </tr> <tr> <td>38</td> <td>37</td> <td>Argentina</td> <td>2020-03-10</td> <td>5.0</td> <td>3</td> </tr> <tr> <td>39</td> <td>38</td> <td>Argentina</td> <td>2020-03-11</td> <td>2.0</td> <td>4</td> </tr> <tr> <td>40</td> <td>39</td> <td>Argentina</td> <td>2020-03-12</td> <td>0.0</td> <td>5</td> </tr> <tr> <td>41</td> <td>40</td> <td>Argentina</td> <td>2020-03-13</td> <td>12.0</td> <td>6</td> </tr> <tr> <td>42</td> <td>41</td> <td>Argentina</td> <td>2020-03-14</td> <td>3.0</td> <td>7</td> </tr> <tr> <td>43</td> <td>42</td> <td>Argentina</td> <td>2020-03-15</td> <td>11.0</td> <td>8</td> </tr> <tr> <td>44</td> <td>43</td> <td>Argentina</td> <td>2020-03-16</td> <td>11.0</td> <td>9</td> </tr> <tr> <td>45</td> <td>44</td> <td>Argentina</td> <td>2020-03-17</td> <td>12.0</td> <td>10</td> </tr> <tr> <td>46</td> <td>45</td> <td>Argentina</td> <td>2020-03-18</td> <td>11.0</td> <td>11</td> </tr> <tr> <td>47</td> <td>46</td> <td>Argentina</td> <td>2020-03-19</td> <td>18.0</td> <td>12</td> </tr> <tr> <td>131</td> <td>130</td> <td>Bahrain</td> <td>2020-02-25</td> <td> </td> <td>1</td> </tr> <tr> <td>132</td> <td>131</td> <td>Bahrain</td> <td>2020-02-26</td> <td>10.0</td> <td>2</td> </tr> <tr> <td>133</td> <td>132</td> <td>Bahrain</td> <td>2020-02-27</td> <td>0.0</td> <td>3</td> </tr> <tr> <td>134</td> <td>133</td> <td>Bahrain</td> <td>2020-02-28</td> <td>3.0</td> <td>4</td> </tr> <tr> <td>135</td> <td>134</td> <td>Bahrain</td> <td>2020-02-29</td> <td>5.0</td> <td>5</td> </tr> <tr> <td>136</td> <td>135</td> <td>Bahrain</td> <td>2020-03-01</td> <td>6.0</td> <td>6</td> </tr> <tr> <td>137</td> <td>136</td> <td>Bahrain</td> <td>2020-03-02</td> <td>2.0</td> <td>7</td> </tr> <tr> <td>138</td> <td>137</td> <td>Bahrain</td> <td>2020-03-03</td> <td>0.0</td> <td>8</td> </tr> <tr> <td>139</td> <td>138</td> <td>Bahrain</td> <td>2020-03-04</td> <td>3.0</td> <td>9</td> </tr> <tr> <td>140</td> <td>139</td> <td>Bahrain</td> <td>2020-03-05</td> <td>3.0</td> <td>10</td> </tr> <tr> <td>141</td> <td>140</td> <td>Bahrain</td> <td>2020-03-06</td> <td>5.0</td> <td>11</td> </tr> <tr> <td>142</td> <td>141</td> <td>Bahrain</td> <td>2020-03-07</td> <td>25.0</td> <td>12</td> </tr> <tr> <td>143</td> <td>142</td> <td>Bahrain</td> <td>2020-03-08</td> <td>0.0</td> <td>13</td> </tr> <tr> <td>144</td> <td>143</td> <td>Bahrain</td> <td>2020-03-09</td> <td>10.0</td> <td>14</td> </tr> <tr> <td>145</td> <td>144</td> <td>Bahrain</td> <td>2020-03-10</td> <td>15.0</td> <td>15</td> </tr> <tr> <td>146</td> <td>145</td> <td>Bahrain</td> <td>2020-03-11</td> <td>85.0</td> <td>16</td> </tr> <tr> <td>147</td> <td>146</td> <td>Bahrain</td> <td>2020-03-12</td> <td>0.0</td> <td>17</td> </tr> <tr> <td>148</td> <td>147</td> <td>Bahrain</td> <td>2020-03-13</td> <td>-6.0</td> <td>18</td> </tr> <tr> <td>149</td> <td>148</td> <td>Bahrain</td> <td>2020-03-14</td> <td>21.0</td> <td>19</td> </tr> <tr> <td>150</td> <td>149</td> <td>Bahrain</td> <td>2020-03-15</td> <td>4.0</td> <td>20</td> </tr> <tr> <td>151</td> <td>150</td> <td>Bahrain</td> <td>2020-03-16</td> <td>0.0</td> <td>21</td> </tr> <tr> <td>152</td> <td>151</td> <td>Bahrain</td> <td>2020-03-17</td> <td>14.0</td> <td>22</td> </tr> <tr> <td>153</td> <td>152</td> <td>Bahrain</td> <td>2020-03-18</td> <td>28.0</td> <td>23</td> </tr> <tr> <td>154</td> <td>153</td> <td>Bahrain</td> <td>2020-03-19</td> <td>22.0</td> <td>24</td> </tr> <tr> <td>155</td> <td>154</td> <td>Bangladesh</td> <td>2020-03-17</td> <td> </td> <td>1</td> </tr> <tr> <td>156</td> <td>155</td> <td>Bangladesh</td> <td>2020-03-18</td> <td>4.0</td> <td>2</td> </tr> <tr> <td>157</td> <td>156</td> <td>Bangladesh</td> <td>2020-03-19</td> <td>3.0</td> <td>3</td> </tr> <tr> <td>158</td> <td>157</td> <td>Belarus</td> <td>2020-03-12</td> <td> </td> <td>1</td> </tr> <tr> <td>159</td> <td>158</td> <td>Belarus</td> <td>2020-03-13</td> <td>15.0</td> <td>2</td> </tr> <tr> <td>160</td> <td>159</td> <td>Belarus</td> <td>2020-03-14</td> <td>0.0</td> <td>3</td> </tr> <tr> <td>161</td> <td>160</td> <td>Belarus</td> <td>2020-03-15</td> <td>0.0</td> <td>4</td> </tr> <tr> <td>162</td> <td>161</td> <td>Belarus</td> <td>2020-03-16</td> <td>9.0</td> <td>5</td> </tr> <tr> <td>163</td> <td>162</td> <td>Belarus</td> <td>2020-03-17</td> <td>0.0</td> <td>6</td> </tr> <tr> <td>164</td> <td>163</td> <td>Belarus</td> <td>2020-03-18</td> <td>15.0</td> <td>7</td> </tr> <tr> <td>165</td> <td>164</td> <td>Belarus</td> <td>2020-03-19</td> <td>0.0</td> <td>8</td> </tr> </tbody> </table>

这是我的df1:

<table> <tbody> <tr> <th> </th> <th> </th> <th>index</th> <th>Country/Region</th> <th>Date</th> <th>NewConfirmed</th> </tr> <tr> <td>1</td> <td>2</td> <td>8</td> <td>Albania</td> <td>2020-03-12</td> <td>11.0</td> </tr> <tr> <td>2</td> <td>10</td> <td>145</td> <td>Bahrain</td> <td>2020-03-11</td> <td>85.0</td> </tr> <tr> <td>3</td> <td>12</td> <td>158</td> <td>Belarus</td> <td>2020-03-13</td> <td>15.0</td> </tr> </tbody> </table>

这是增加了列的输出:

<table> <tbody> <tr> <th> </th> <th> </th> <th>Country/Region</th> <th>Date_x</th> <th>NewConfirmed_x</th> <th>index_by_country_x</th> <th>index</th> <th>Date_y</th> <th>NewConfirmed_y</th> <th>index_by_country_y</th> </tr> <tr> <td>1</td> <td>0</td> <td>Albania</td> <td>2020-03-10</td> <td> </td> <td>1</td> <td>8</td> <td>2020-03-12</td> <td>11.0</td> <td>3</td> </tr> <tr> <td>2</td> <td>1</td> <td>Albania</td> <td>2020-03-11</td> <td>2.0</td> <td>2</td> <td>8</td> <td>2020-03-12</td> <td>11.0</td> <td>3</td> </tr> <tr> <td>3</td> <td>2</td> <td>Albania</td> <td>2020-03-12</td> <td>11.0</td> <td>3</td> <td>8</td> <td>2020-03-12</td> <td>11.0</td> <td>3</td> </tr> <tr> <td>4</td> <td>3</td> <td>Albania</td> <td>2020-03-13</td> <td>10.0</td> <td>4</td> <td>8</td> <td>2020-03-12</td> <td>11.0</td> <td>3</td> </tr> <tr> <td>5</td> <td>4</td> <td>Albania</td> <td>2020-03-14</td> <td>5.0</td> <td>5</td> <td>8</td> <td>2020-03-12</td> <td>11.0</td> <td>3</td> </tr> <tr> <td>6</td> <td>5</td> <td>Albania</td> <td>2020-03-15</td> <td>4.0</td> <td>6</td> <td>8</td> <td>2020-03-12</td> <td>11.0</td> <td>3</td> </tr> <tr> <td>7</td> <td>6</td> <td>Albania</td> <td>2020-03-16</td> <td>9.0</td> <td>7</td> <td>8</td> <td>2020-03-12</td> <td>11.0</td> <td>3</td> </tr> <tr> <td>8</td> <td>7</td> <td>Albania</td> <td>2020-03-17</td> <td>4.0</td> <td>8</td> <td>8</td> <td>2020-03-12</td> <td>11.0</td> <td>3</td> </tr> <tr> <td>9</td> <td>8</td> <td>Albania</td> <td>2020-03-18</td> <td>4.0</td> <td>9</td> <td>8</td> <td>2020-03-12</td> <td>11.0</td> <td>3</td> </tr> <tr> <td>10</td> <td>9</td> <td>Albania</td> <td>2020-03-19</td> <td>5.0</td> <td>10</td> <td>8</td> <td>2020-03-12</td> <td>11.0</td> <td>3</td> </tr> <tr> <td>11</td> <td>10</td> <td>Bahrain</td> <td>2020-02-25</td> <td> </td> <td>1</td> <td>145</td> <td>2020-03-11</td> <td>85.0</td> <td>16</td> </tr> <tr> <td>12</td> <td>11</td> <td>Bahrain</td> <td>2020-02-26</td> <td>10.0</td> <td>2</td> <td>145</td> <td>2020-03-11</td> <td>85.0</td> <td>16</td> </tr> <tr> <td>13</td> <td>12</td> <td>Bahrain</td> <td>2020-02-27</td> <td>0.0</td> <td>3</td> <td>145</td> <td>2020-03-11</td> <td>85.0</td> <td>16</td> </tr> <tr> <td>14</td> <td>13</td> <td>Bahrain</td> <td>2020-02-28</td> <td>3.0</td> <td>4</td> <td>145</td> <td>2020-03-11</td> <td>85.0</td> <td>16</td> </tr> <tr> <td>15</td> <td>14</td> <td>Bahrain</td> <td>2020-02-29</td> <td>5.0</td> <td>5</td> <td>145</td> <td>2020-03-11</td> <td>85.0</td> <td>16</td> </tr> <tr> <td>16</td> <td>15</td> <td>Bahrain</td> <td>2020-03-01</td> <td>6.0</td> <td>6</td> <td>145</td> <td>2020-03-11</td> <td>85.0</td> <td>16</td> </tr> <tr> <td>17</td> <td>16</td> <td>Bahrain</td> <td>2020-03-02</td> <td>2.0</td> <td>7</td> <td>145</td> <td>2020-03-11</td> <td>85.0</td> <td>16</td> </tr> <tr> <td>18</td> <td>17</td> <td>Bahrain</td> <td>2020-03-03</td> <td>0.0</td> <td>8</td> <td>145</td> <td>2020-03-11</td> <td>85.0</td> <td>16</td> </tr> <tr> <td>19</td> <td>18</td> <td>Bahrain</td> <td>2020-03-04</td> <td>3.0</td> <td>9</td> <td>145</td> <td>2020-03-11</td> <td>85.0</td> <td>16</td> </tr> <tr> <td>20</td> <td>19</td> <td>Bahrain</td> <td>2020-03-05</td> <td>3.0</td> <td>10</td> <td>145</td> <td>2020-03-11</td> <td>85.0</td> <td>16</td> </tr> <tr> <td>21</td> <td>20</td> <td>Bahrain</td> <td>2020-03-06</td> <td>5.0</td> <td>11</td> <td>145</td> <td>2020-03-11</td> <td>85.0</td> <td>16</td> </tr> <tr> <td>22</td> <td>21</td> <td>Bahrain</td> <td>2020-03-07</td> <td>25.0</td> <td>12</td> <td>145</td> <td>2020-03-11</td> <td>85.0</td> <td>16</td> </tr> <tr> <td>23</td> <td>22</td> <td>Bahrain</td> <td>2020-03-08</td> <td>0.0</td> <td>13</td> <td>145</td> <td>2020-03-11</td> <td>85.0</td> <td>16</td> </tr> <tr> <td>24</td> <td>23</td> <td>Bahrain</td> <td>2020-03-09</td> <td>10.0</td> <td>14</td> <td>145</td> <td>2020-03-11</td> <td>85.0</td> <td>16</td> </tr> <tr> <td>25</td> <td>24</td> <td>Bahrain</td> <td>2020-03-10</td> <td>15.0</td> <td>15</td> <td>145</td> <td>2020-03-11</td> <td>85.0</td> <td>16</td> </tr> <tr> <td>26</td> <td>25</td> <td>Bahrain</td> <td>2020-03-11</td> <td>85.0</td> <td>16</td> <td>145</td> <td>2020-03-11</td> <td>85.0</td> <td>16</td> </tr> <tr> <td>27</td> <td>26</td> <td>Bahrain</td> <td>2020-03-12</td> <td>0.0</td> <td>17</td> <td>145</td> <td>2020-03-11</td> <td>85.0</td> <td>16</td> </tr> <tr> <td>28</td> <td>27</td> <td>Bahrain</td> <td>2020-03-13</td> <td>-6.0</td> <td>18</td> <td>145</td> <td>2020-03-11</td> <td>85.0</td> <td>16</td> </tr> <tr> <td>29</td> <td>28</td> <td>Bahrain</td> <td>2020-03-14</td> <td>21.0</td> <td>19</td> <td>145</td> <td>2020-03-11</td> <td>85.0</td> <td>16</td> </tr> <tr> <td>30</td> <td>29</td> <td>Bahrain</td> <td>2020-03-15</td> <td>4.0</td> <td>20</td> <td>145</td> <td>2020-03-11</td> <td>85.0</td> <td>16</td> </tr> <tr> <td>31</td> <td>30</td> <td>Bahrain</td> <td>2020-03-16</td> <td>0.0</td> <td>21</td> <td>145</td> <td>2020-03-11</td> <td>85.0</td> <td>16</td> </tr> <tr> <td>32</td> <td>31</td> <td>Bahrain</td> <td>2020-03-17</td> <td>14.0</td> <td>22</td> <td>145</td> <td>2020-03-11</td> <td>85.0</td> <td>16</td> </tr> <tr> <td>33</td> <td>32</td> <td>Bahrain</td> <td>2020-03-18</td> <td>28.0</td> <td>23</td> <td>145</td> <td>2020-03-11</td> <td>85.0</td> <td>16</td> </tr> <tr> <td>34</td> <td>33</td> <td>Bahrain</td> <td>2020-03-19</td> <td>22.0</td> <td>24</td> <td>145</td> <td>2020-03-11</td> <td>85.0</td> <td>16</td> </tr> <tr> <td>35</td> <td>34</td> <td>Belarus</td> <td>2020-03-12</td> <td> </td> <td>1</td> <td>158</td> <td>2020-03-13</td> <td>15.0</td> <td>2</td> </tr> <tr> <td>36</td> <td>35</td> <td>Belarus</td> <td>2020-03-13</td> <td>15.0</td> <td>2</td> <td>158</td> <td>2020-03-13</td> <td>15.0</td> <td>2</td> </tr> <tr> <td>37</td> <td>36</td> <td>Belarus</td> <td>2020-03-14</td> <td>0.0</td> <td>3</td> <td>158</td> <td>2020-03-13</td> <td>15.0</td> <td>2</td> </tr> <tr> <td>38</td> <td>37</td> <td>Belarus</td> <td>2020-03-15</td> <td>0.0</td> <td>4</td> <td>158</td> <td>2020-03-13</td> <td>15.0</td> <td>2</td> </tr> <tr> <td>39</td> <td>38</td> <td>Belarus</td> <td>2020-03-16</td> <td>9.0</td> <td>5</td> <td>158</td> <td>2020-03-13</td> <td>15.0</td> <td>2</td> </tr> <tr> <td>40</td> <td>39</td> <td>Belarus</td> <td>2020-03-17</td> <td>0.0</td> <td>6</td> <td>158</td> <td>2020-03-13</td> <td>15.0</td> <td>2</td> </tr> <tr> <td>41</td> <td>40</td> <td>Belarus</td> <td>2020-03-18</td> <td>15.0</td> <td>7</td> <td>158</td> <td>2020-03-13</td> <td>15.0</td> <td>2</td> </tr> <tr> <td>42</td> <td>41</td> <td>Belarus</td> <td>2020-03-19</td> <td>0.0</td> <td>8</td> <td>158</td> <td>2020-03-13</td> <td>15.0</td> <td>2</td> </tr> </tbody> </table>